Change speed gear system



April 30, 1940. 'J. CAHN 2,198,958

CHANGE SPEED GEAR SYSTEM Filed April 21-, 1937 2 Sheets-Sheet 1 J. CAHNCHANGE SPEED' GEAR SYSTEM April 30, 1940.

Filed April 21, 1937 2 Sheets-Sheet 2 q I I I 7 a I I 1 lffwA "Joseph"calm, Liege, nelgiiiliigassign r or one; half, to Hermann Feig enbaum,[ieige,, Belgium If. Q I 4 1 Application April 21, :193 7', Serial"No..138,249 In BelgiumApi'il' 27511936 .2 r;

Claims. moi. 74 325) ing gear being radially displaceable relatively tothe said hub or the 1ike.-"-

Preferably the radial displacement of the driving gear and theqvariationin the pitch radius of thedriven gear-are efiected in synchronism andare of -equal=.dimensions,-and since the said diameter may be varied toariyextent (within reasonable limits) an indefinite number of differentspeed ratios may be provided. a 7 Two applications of the invention, toathreespeed gear and tota multiple-speed gear, ar shown in thedrawings,in which:

: Figure .lhisia perspective exploded view of the three-speed gear and--.-Figure is an axial section throug h the threespeed gear according toFigure 1, showing the title. variousxcomponent parts in assembledposition.

@Figures3; 4:and 5 are views of details; I

Figurefi, is'a viewof the multiple-speed-gear permitting "to. changethe'speed in a continuous manner, the difierent elements being partly.

broken away,.-for showingthe elements-situated behind c i ,4 a

.The change-speed gear shown in the said drawings comprises an annularchain-driven wheel 9 which is mounted around the spindle I8 40;; of therearroad wheel of'a cycle orsimilar vehicle intermediate the hub cf thesaid wheel and the lug 25 0f therear fork of the cycle frame, the

saidsprocketbeing-adapted to be displaced radiallywwith respect tothesaid spindle and being 4csprovided with a system of internal ratchetteeth l0. 7

This annular sprocket wheel is located by a set of balls 14 which areadapted to run around "the periphery of a" disc-like element:=l2, theouter corrface; that'is the face remote from the hub 24, of

which is recessed, with the exception of-the portion 26. v v

A' lever or'key 21 is rotatablylmounted upon the spindle ['8' and is sohoused within the relili c cessed-outer-face of the vdisc l2 that itsperiphery.

bears upon theiedge 21a of theprojecting portion 26 of the said'disc andis adapted-to displace the disc; l2 and'sprocket 9 radially with respectto the spindle as describedb'elow. To permit vof this radical movementbeing imparted to the said disc and sprocket, the edge of the lever issomefiled that it comprises 'threearcuate portions 28, 30- and 33, whichare located at successively increasing distances from thespindle l8 andseparated from one another by the steps or cams-28- and 32. The leveralso comprises an arm 34 to thezfore end of which an oscillatoryanchorlike member 35 is attached, one end of a rod 31 being connectedtothe said-member 35 whilst its other end terminates at some'part of thecycle within reach of the vcyclistls hand. a I I Normally the lever 21is-retainedwithin the recessediface of the disc l2 by a plate 38, whichis also carriedupon the spindle 18 and this plate is provided onitsinner face with a pin 39 which projects into-a. radial slot or-groove 40provided inthe projecting disc portion 26 and, since the plate 38-isfixedrelativelyto the cycle frame, thispin guides the radial movementofthe disc IZWheIi-dispIaced by'the stepped periphery of the lever 21.The outer face of the plate 38 is provided-with a projecting sleeve 42-which engages with the fork-lug 25 and'prevents the said platefromfrotating on the spindle, and this sleeve-may be mounted in any oneof a system-ofv holes 43 formedin the plate 38 so that it may engage'with the lug 25 whatever the position of the-latter may be upon thecycle fork.

A systemofthree toothed sectors 45 are located on the opposite side ofthe annular sprocket to the'disc "l2, these sectors being located in theplaneof the ratchet-teeth [0 with which they are adapted to mesh eithersimultaneously as-a clutch or, successively as a gear according towhether thedirect or a geared speed is selected.

These toothed sectors aresupported on or carriedby pins.145'embodyingguiding portions 55 (see Figure 3) which are adapted topassthrough.arcuate slots 41 of a toothed plate 48 into radial slots 49 of a guideplate 50 fastened to the end of the hub 24 of the cyqleroad wheel, andthe sides of the. arcuate slots 41 are so stepped thatv they have thesame profile as the stepped edge 28, 29,30, 321 and 33 of the lever 21,with the exception that the steps are arranged in the reverse;order,,:that is vtorsay, the, arcuate edge nearest the spindle I8 islocated at the right-e hand end of. the slot instead of the left handend.

Each sector 45is provided with a spring 52 t which is secured; to,the.lcompl mentary p ri, .4

and bears against a shoulder of similar projection 53 adjacent one endof the sector so that it tends to rotate the said sector and retain itin mesh with the ratchet teeth [0.

The above component parts are locked or retained in their assembledpositions by a nut 44 which is screwed on to the end of the spindle F8.As shown in Figure 2 plate 50 is screwed upon a right hand thread 24a ofhub 24 and is retained by a nut 24b screwed on a left hand thread 240 ofhub 24, (plate 50 could as well be keyed on the hub 24) and plate 48isrotatablydisposed on a hub portion 50a of plate 50. Moreover it is tobe observed that the anchorlike member 35 which serves to cooperate withthe toothed edge of plate 48 is located on a pivot 35a fixed to arm 34and is automatically held out of engagement with said toothed edge bythe action of a spring 35b fixed to the pivot 35a and profiled cam edgeof the lever or key 21 bears against the cam following edge 21a of theprojecting disc-portion 26, the said edges being retained in intimatecontact by a tension spring 5211 which is connected between the disc 12and the lug 25 or other suitable anchorage on the cycle fork; in

this position the sprocket and disc unit is concentric with thespindleI8.

If the lever or key Zlis now rotated about the spindle [8 in thedirection indicated by the arrow (Figure-l) by the manual. actuation ofthe rod 37, one arm of the anchor-like member. 35 engages,

sector-supporting pins 46, that the said guides are taken out of theslot portions furthest from the spindle l8 into the adjacent portionswhich are-closer, to the said spindle so that the three toothed sectors,whilst still remaining spaced apart, are closed in radially towards oneanother,-

the radial displacement of each of the sectors being equal to the radialdisplacement of the unit 9, i2. Hence one of thesaidsectors will move inunison and remain inmesh with'the ratchet teeth Iil,'whereas the othertwo sectors willmove away from the said teeth, and the said sectors,although still heldwrigidly apart, constitute a composite gear which isof smaller diameter than the gear H1, is eccentric to the latter and isalso smaller than theinitial composite clutch-gear composed by the fullyexpanded-sectors 45. Asthe chain driven sprocket 9 rotates, each sectorof the composite sector-gear will mesh successively with the ratchetwheel Hi and the ratio of the gear Hi to the gear 45 will cause anoverdrive of the plate 50 and the cycle hub and produce ahigher gearspeed namely second and middle gear.

By continuing the movement of the control anchor lever 35 the arcuateportion 33 of the lever 21 moves into contact with the edge 21a andimparts an additional lateral movement to the unit 9, l2;simultaneously, the portions of the slots 41 nearest to the spindle,will engage the sector pinguides 55 and fully contract or close in thesaid sectors to form a continuous ring which is eccentric to and in meshwith the internal ratchet gear Third or high speed is thus obtained.

To reduce the gear speed the rod 31 is moved in the reverse direction soas to displace the cam leverzl backwards when the unit 9, I2 is returnedtowards its initial position by the spring 52a and V the other arm ofthe anchor-like member 35 engages the toothed periphery of the plate 48and moves the latter in unison with the said cam lever When the cyclistis free-wheeling in any gearspeed the toothed sectors 45 will over-run.the

ratchet teeth Ill by virtue of: the springs 52. It will beinoticed thatthe driving gear and. chain sprocket or the like are rotatably mountedon a. support which is radially vdisplaceable on the spindle of the,road. wheel transversely to the main. direction of the sprocket drivingchain or thelike, 9a. (Figure 2:).

In change speed gears according to the present inventiomapplied to hubswith back-pedaling brake mechanism, the inwardly extending teeth ill ofthe driving gear and theteeth of the sectors 45 of the driven gear willbe, preferably straight that is, of the spur-tooth shape (see. Figure4)- so that such gears will remain-in mesh with each other andcooperatein both directions of rotation, forward actionv causing propulsion,rearward action braking and no action free-wheeling.

According to the example shown in Figure 4 the toothed sectcrsj45- areengaged by an elastic split ring or springs, 54 whichgopen or close inaccordance with whether the composite gear combined with the said ringor springsis expanded or contracted. v I

The transmission system 31=of any usual type, for instance a rod orcable, system, may be actuated for, instance by means of a double armedlever 56, 51 (see Figure 5) pivotedat 58 to a plate t9 which isattached-to any suitable part of the vehicle for instance to thesteering head tube. I

The lever-arm 5.8 is provided with any suitable kind of locking system,for. instance such as the spring actuated slide B0--6i serving to enterinto one of the notches 62, 63, 64, etc on the plate 69 according ;tothe position in which the system 3 and the parts controlledby it are tobe arrested (first, second, third, etc., speed).

Themultipleespeed-gear shown in Figure 6 differs from the three-speedgear according to Figures 1 and 2, in that instead of stepped slots 41',there are? providedin plate 48 continuous slots ll for displacing thetoothed sectors '45-" (which, can biz-toothed only on one side of theaxes 46,.whereas their end on the other side of said axes maybe simplysmooth) with-their axes 4b; and sliding 'supDQrts towards and away fromeach other. The supporting plate l2 and the leveril with arm 34, makingpart of the gear according'to Figure 6 are provided, withcooperating'continuous cam portions 65, 66 of a shape corresponding tothat of slots 47'. In this case'the 's'etsoi parts 45', 46, 55 may have.the tendency, due'to the working stress, tomove towards the innerportion of the slots '41, this being impeded, by at least one pawl 16pivoted to. platellfi and cooperating with acorrespOhdingly toothedportion 11 on plate 50. The plate 48 is provided, beneath the pawl I6with for instance two small cavities such as 18, I9 whereas the pawl isprovided for instance with a spring actuated ball (not shown) capable toenter into the one or the other of said cavities, according to theposition of the pawl. The plate 50 is provided moreover with twoabutments 80 and 8|. Abutment 80 lifts the pawl 16 as soon as, by themanipulation of the key 34, 66 with its member 36, 55 in the directionof the arrow,

the plate 48, with its slots 41, has been brought a little beyond theposition of lowest speed, the pawl 16 remaining in the lifted positionby virtue of its spring actuated ball entering then into the cavity 18.By the manipulation of the key 34, '66 in the opposite direction, theplate 48 is then brought to the position of greatest speed at which theabutment 8| pushes the pawl down into engagement with the toothedportion" of plate 50, the spring actuated ball of the pawl 16 being thistime engaged into the cavity 19 thus holding the pawl in cooperativeengagement with the toothed portion 11 of plate 50. If now the key, 66with member 35 is again operated 'in the direction of the arrow, forinstance each time through the pitch of one tooth of the toothed portionof plate 50, there will be obtained successively as many differentspeeds, from the greatest to the lowest, as there are different teeth 11between abutments Bland 80.

I claim:

1. A change speed gear for cycles comprising in combination a stationaryspindle, a support radially displaceable on said spindle, a driving gearwheel having inwardly extending teeth rotatably mounted on said support,a hub rotatable on said spindle, a driven gear wheel of variablepitch-diameter fixed to said hub and meshing with said inwardlyextending teeth of the driving gear wheel, and means mounted on saidspindle and adapted to be moved only in parallel direction with respectto the plane of the pitchcircle of said gear wheels, to radiallydisplace said support and to vary the pitch-radius of said driven gearwheel.

2. A change speed gear for cycles according to claim 1, in which saidmeans for radially dis,- placing said driving gear-support are adaptedto perform synchronous and corresponding variations in pitch-radius ofsaid driven gear.

3. A change speed gear for cycles, comprising in combination a spindlefor a road-wheel, a support radially displaceable on said spindle, adriving gear wheel having inwardly extending teeth rotatably mounted onsaid support, a chainsprocket making part of said driving gear wheel, ahub of a road-wheel rotatable on said spindle, av driven gear wheel ofvariable pitch-diameter fixed to said hub and meshing with said inwardlyextending teeth of the driving gear wheel, a driving chain cooperatingwith said chain sprocket, and means mounted on said spindle and adaptedto be moved only in parallel direction with respect to the plane of thepitch-circle of said gear wheels, to displace said support transverselyto the main direction of said driving chain and to vary simultaneouslythrough corresponding extents the pitch-radius of said driven gearwheel. 4. A change speed gear for cycles comprising in combination aspindle for a road-wheel, a support radially displaceable on saidspindle, a cam portion on said support, a cam member rotatably mountedon said spindle and cooperating with said cam portion of said support, adriving gear wheel having inwardly extending teeth rotatably mounted onsaid support, a chain-sprocket making partof said driving gear wheel, ahub of a road wheel rotatable on said spindle, a driven gear wheel ofvariable pitch-diameter fixed to said hub and meshing with said inwardlyextend-.

teeth and making part of a chain-sprocket said driving gear ring andsprocket being rotatably supported by a disc located'inside of saidchain sprocket and radially displaceable on said spindle, a cam-portionon said disc, a cam-lever ro-" tatably mounted on said spindle andcooperating with said cam-portion of said support, a rearroad-wheel-hubrotatable on said spindle, a driven gear-wheel of variablepitch-diameter fixed to said hub and meshing with said inwardlyextending teeth of the driving gear wheel, said gear wheel of variablepitch-diameter comprising a pitch-diameter regulating disc with atoothed periphery, rotatable with respect to said hub, a toothed memberarticulated to said camlever and cooperating with the toothed peripheryof said regulating disc, and means for simultaneously actuating saidcam-lever and said toothed member articulated to the cam-lever.

JOSEPH CAHN,

